The invention concerns the enrichment in calcium of a milk, a milk-based beverage or a dietetic product.
Calcium is an important element in the nutrition of mammals, in particular humans. Calcium is necessary for the formation of bones and the maintenance of their quality and is indispensable for metabolism.
Milk products, in particular milk, are an important source of calcium. Unfortunately, many people do not consume the quantity of milk necessary for their nutritional needs. One liter of milk generally contains approximately 1250 mg of calcium.
The enrichment in calcium of milk or of dietetic products having a composition similar to that of milk encounters technological problems when it is desired to manufacture non-acid liquid products, in particular long life products, for example ultra-pasteurized or sterilized products. In point of fact, many potentially useful calcium salts are soluble in water, so that the solution consisting of adding these salts directly to the raw material and then subjecting the mixture to heat treatment, in particular ultra-pasteurization or sterilization, is not generally possible, since this heat treatment leads to a finished product which is degraded from the point of view of physico-chemical stability and organoleptic properties. The addition of insoluble salts before heat treatment does not have the afore-mentioned disadvantages, but on the other hand these salts settle rapidly at the bottom of the package.
A solution to this problem is provided, for example, by the process according to European Patent Application Publication No. 0285795. It consists of adding thickening or gelling agents to a suspension of calcium salt, of heat treating the mixture and then aseptically metering it in a production line for a previously sterilized milk product.
The addition of calcium salts and polyphosphate to a whole milk before UHT treatment is known, for example, from Australian Patent Application No. 88768182. In this patent application, the addition of a calcium salt in the presence of polyphosphate aims at stabilizing the milk by preventing it gelling with time during storage.